^ I also wouldn't rule out the green tea (or white) yet either. Cut it out for a while to see if you get better, sure. White tea is the same plant as green or 'black.' so you need to avoid it for a bit as well.
Rooibos is good, but it's purported to be one of the teas that absorb a lot of flouride from water, so the next thing to know is the origins of the tea and whether they have flourinated water or water naturally high in flouride.
Hibiscus is also wonderful, as a cold drink.
Nettle tea could be very beneficial to you. It's a source of minerals as the plants have deep roots that gather a lot of nutrients from the soil. And it's antihistimine.
There's lemongrass. Clove if you'd like a spice tea. You'll find lots of eleborate recipes, but don't bother. You drop a clove or two in your cup of hot water. Cloves top the list of anti-oxidants. That's why it's so damn spicy.
And there's ginger. Although I usually add a slice of ginger to just about any tea I'm drinking.
Also, plain hot cocoa - that's cocoa powder and water. It might take a little to bit to get used to since you are probably accustomed to a sweet creamy drink.